1. Field of the Invention
The invention relates to an optical disc case structure. More particularly, the invention relates to an ultra-thin case structure for receiving an optical disc having a diameter of 8 cm.
2. Description of the Related Art
Along with the development of information technology, the amount of numerical data that is transferred, processed, and stored becomes tremendous. Optical storage discs, such as compact discs, are presently the principal supports of numerical data storage. The optical discs are conventionally placed within a disc case.
Referring to FIG. 1 and FIG. 2, two perspective views schematically show the structure of a conventional optical disc case. The conventional disc case usually receives a standard disc 10 having a diameter of 12 cm. The disc case is constructed from a bottom cover 1 and a top cover 2 assembled with each other. The bottom cover 1 includes a bottom board 11 whose front and rear outer peripheries are respectively provided with front and rear peripheral projections 12 that are symmetrical to each other. Each front/rear peripheral projection 12 is composed of two projecting elements that are spaced apart from each other via a groove 15 and, furthermore, respectively define a flange 13 via a recessed portion 14 approximately located at a central position of each projecting element. Left and right peripheral projections 16, 17 further project respectively from a left outer periphery and a right outer periphery. An outer surface of the right peripheral projection 17, at a central portion, is further recessed into an opening groove 171. Each front/rear peripheral projection 12 extends beyond the left peripheral projection 16 into a connecting segment 19 provided with a pivot axle 191.
A top surface of the bottom board 11 is provided with short arcuate projections 111 that are coaxial to one another to fit an outer diameter of the disc 10. The short arcuate projections 11 are conventionally four arcuate projections placed vis-a-vis four corners of the bottom board 11, defined by the connection of the front/rear peripheral projections 12 with the left and right peripheral projections 16, 17. Inwardly from the short arcuate projections 111, long arcuate projections 113, conventionally thinner and smaller, are placed on the bottom board 11 respectively vis-a-vis the left and right peripheral projections 16, 17. The long arcuate projections 113 are coaxial to each other with a length greater than two corresponding short arcuate projections 111. On the top surface of the bottom board 11, a projecting ring 112 is arranged vis-a-vis a central periphery of the central hole of the disc 10 while a holding member 18 is further placed vis-a-vis the central hole of the disc 10. The holding member 18 is composed of at least three portions. Each portion respectively has an arcuate positioning tongue 181 and an arcuate holding tongue 182 to position and hold the disc 10, as shown in FIG. 2 through FIG. 4. A protuberance 184 is located on an upper portion of the outer surface of the arcuate holding tongue 182 to position and hold the disc 10 by engaging its central hole. The arcuate positioning tongue 181 has a lateral contour longer than that of the arcuate holding tongue 182, and an outer surface of the tongue 181 is upwardly curved into a rounded profile 183.
The top cover 2 includes a top board 21 whose left, front, and rear outer peripheries are respectively provided with projecting peripheral segments 24, 22, 23, while the right outer periphery is opened. Furthermore, connecting segments 26 are placed proximate to the left peripheral segment 24 and respectively spaced apart from the front/rear peripheral segments 22, 23 via spacing grooves 25. A pivot hole 261 is defined through each connecting segments 22, 23 to engage with the pivot axle 191 of the connecting segments 19. Attachment grooves 221, 231 are further defined in the front and rear peripheral segments 22, 23 to engage with protuberances 121 respectively formed on the front and rear peripheral projections 12, when the bottom and top covers 1, 2 are closed by folding onto each other.
On the top cover 21, a long holder bar 27 is placed proximate to the left peripheral segment 24 while pair of short holder bars 28 is placed proximate to the right peripheral side of the top cover 21. A pair of transversal flanges 29 respectively project inwardly from an inner surface of the front and rear peripheral segments 22, 23, and engage the inwardly recessed portions 14 of the bottom board 11. A slot 291 is further respectively defined through each transversal flange 29 of the top board 21.
With the above case structure, the disc 10 is held in or released from the disc case by means of the protuberance 184 and the resilience property of the material that constitutes the arcuate holding tongue 182. The deviation of the arcuate holding tongue 182 is therefore limited. The above conventional case structure may be subjected to various deficiencies, as described hereafter. For example, the protuberance 184 may be easily broken or the arcuate holding tongue 182 may be deformed. Furthermore, the bottom surface of the arcuate holding tongue 182 is coplanar with the bottom surface of the bottom board 11. As a result, the pressure exerted on the arcuate holding tongue 182, when the disc 10 is taken, can generate a negative stress on the contact portion of the bottom surface of the arcuate holding tongue 182 with the bottom surface of the bottom board 11. Although a resulting deviation may not be significant, this deficiency however may cause the holding member 18 not to be durable. Therefore, a ringed recess 185 is usually defined on the periphery of the holding member 18 to relieve stress. However, this disposition does not provide satisfactory results with respect to the durability of the holding member.
It is therefore a principal object of the invention to provide an optical disc case structure that overcomes the above problems by having a more reliable holding member. It is another object of the invention to provide an optical disc case structure that has a reduced dimensional size so that it can be disposed in a smaller occupation space.
Furthermore, it is another object of the invention to provide an optical disc case structure that allows an easy opening of the disc case and an easy take-up of the disc placed therein.
To accomplish the above and other objectives, an optical disc case structure of the invention comprises a bottom cover and a top cover that are pivotally mounted to each other. The bottom cover respectively comprises a bottom board, a front peripheral projection, a rear peripheral projection, a take-up/put-in groove, a protruding ring, a left peripheral projection, a right peripheral projection, a plurality of first connecting segments respectively provided with pivot axles, and a holding member. The top cover comprises a top board, a left peripheral segment, a front peripheral segment, a rear peripheral segment, and a plurality of second connecting segments respectively provided with pivot holes. The bottom cover and the top cover pivotally assemble with each other via the pivot axles engaging the pivot holes. The holding member comprises at least two pairs of arcuate positioning tongues and arcuate holding tongues. The arcuate positioning and holding tongues together form the holding member that projects approximately perpendicular to the bottom board to engage a central hole of a disc. Each arcuate positioning tongue has an inner surface thereof upwardly extending in inclined and taper manners while an outer surface thereof upwardly bends into a rounded profile. Each arcuate holding tongue is spaced apart from and adjacent to at least one arcuate positioning tongue. Each arcuate holding tongue is connected to the bottom board via a connection in which a U-shaped clearance is defined. The clearance is cut through the bottom board so that the arcuate holding tongue is thereby enabled to resiliently deviate. Furthermore, each arcuate holding tongue is integrally inclined outwardly meanwhile projecting toward the received disc. A bottom surface of each arcuate holding tongue is connected to an outer bottom surface of the bottom board. The bottom surface of the arcuate holding tongue appears as a face upwardly inclined from the outer bottom surface of the bottom board, formed from a notch that is accomplished into the outer bottom surface of the bottom board. A ringed groove is further defined between an inner top surface of the bottom board and the arcuate holding tongue.
To provide a further understanding of the invention, the following detailed description illustrates embodiments and examples of the invention, this detailed description being provided only for illustration of the invention.